Manufacture of hollow bodies from fibrous pulp



Dec. 7 1926.

R. HAAS MANUFACTURE OF HOLLOW BODIES FROM FIBROUS PULP Filed Nov. 12. 19 25 fnrenfo R. Haas ther improvement of 1 while being 2 such a-manner as t Pumice Dec. 7, 1926.,

UNl-TEDSTA ns {PAT BUIDOLE HAAS. OF BAJJEiN-B ADEN, GERMANY.

MANUFACTURE or no Low BonIEs mom DFIIBEOUS PULP.

Application filed November 12, 1925; Serial lfl'o. 68,691, and in Germany November 24, 1924. a"

It has already been proposed vto manufacture hollow bodies from fibrous pulp by letting the quantity of fibrous pulp required each timeflow into a mould having pervious walls and thereupon efl'ecting the removal of water and the drying by means of a heated gaseous pressure medium.

The presentinvention constitutes a .fursuch methods and consists more particularly in this, that the preliminary container which is interpolated between the supply pipe for the fibrous pulp and the inouldis shut off from the mould filled, that the contents, after the means for shutting off the said pipe have been opened again, are transferred to themould and that the heated gaseous pressure medium is allowed to enter between the preliminary container and the mould. in

circumvent the preliminary container. g

In the accompanying drawing three constructional examples of the invention are I shown diagrammatically.

Figure I is a vertical' section of the apparatus used. Figure II is a modification also 'in vertical section showing the mold in dposition.

Figure III is a further mo lfiGfllJlOIl of a partof the device.

' I The fibrous pulp enters throughthe valve a from the supplypipeinto the preliminary container 6 b When the latter has been suflieiently filled the valve 0 which has so container 71 b into the mould d. Instead of this the piston may for instance itself beused for forcing the pulp into the mould, in which case the preliminary container will take the place of the delivering member.

similar effect may be obtained by the preliminary container being replaced by any suitable pulp pump of a known form (Fig.

will be obvious, that at the end of each displacementof the fibrous, pulp, out of the preliminary container a-certain quanbe forced out of the mould by the gaseous heating medium entering at 0, before the actual drying operation commences. For accelerating-the operation in this case as well a separate gaseous pressure medium may be introduced for instance through the valve 2' before the heating medium is admitted at e. Alternatively, the arrangement according to the present invention may be such' that the residual liquid referred to ,above is removed from the mould to a reater or less extent through 'a pipe is which extends into the mould d and is controlled by a valve 1,

for which purpose the pressure of the gaseor pressure medium entering at ous heating be utilized.- The emerging re- 6 or "5 ma si iual liquld may be introduced again at any far out bit the mould d from the preliminary v container is opened. By this means the fibrous pulp is passed into the mould d.

When this has taken place, the valve 0 is closed and the gaseous heating medium is allowed to flow in through. the valve e. While it is drying the hollow .body tobe moulded in the mould d, afresh filling can flow through the valve a into the preliminary container 17 b f Inthe example shown in Figure 2 the preliminary container 6 is of variable size, for

instance by a piston f being so arranged as to be capable of being withdrawn to a. greater or less extent by means of the spindle g and .the hand-wheel h. By this means the weight of the body to be moulded can be accurately gauged. r

Through the valve 21 i any suitable gas.- eous pressure medium maybe introduced for the purpose of accelerating the passage of the fibrous pulp from the preliminary suitable pointin the path of the fib whereby it is caused to travel in a close circuitwithout an loss of ulp.

The new metho hasi th following advantages: A

1. An accurate measurement of 'the fibrous pulp and consequently great uniformity o theproducts. 2. The avoidance-of heat losses through the employment of the preliminary container. 3. A more uniform drying through the 'displacement of the residualliquid without sacrificing the ad antages provided by a mouldwhich is fill d from above.

What I claim is:

ous pulp,

1'. A method of manufacturing hollow bodies from fibrous pulp in mouldsrwith pervious walls by the use of a gaseous pressure medium, consisting in this-that'the fibrouspulp' is first passed into a preliminary container whilst the same is shut oi; from themould, whereupon communication is established between the cbntainer and the mould, whereby water is removed from the pulp in the mould, and a aseous heating medium is then admitted into the mould Without passing through the preliminary container, as and for the purpose set forth.

2. A method as claimed in claim 1, and consisting in this that While the mass of fibrous pulp contained in the mould is being dried by the gaseous heating medium the fresh supply of pulp is admitted into the preliminary container for the next moulding operation, as set forth.

3. A method as claimed in claim 1, and consisting in this that after the fibrous pulp has been conveyed from the preliminary container into the mould the liquid remaining in the mould itself and in the supply pipe for the same is forced out of the mould by a separate gaseous pressure medium.

4. A method as claimed in claim 1, and in which the removal of the Water is accelerated by a greater or less portion thereof being 'forced out upwardly through a pipe extending into the mould under the action of the medium admitted to the mould, as set forth.

5. An apparatus for manufacturing hollOW bodies from fibrous pulp, comprising in combination a container, a supply pipe for supplying pulp to the container, a pervious mould, a connecting pipe between the container and the mould, a valve in the said 80 supply pipe, a valve in the said connectin ipe, means for removing the residual liquiu rom the mould and means for admitting a gaseous heating medium directly into the mould, as and for the purpose set forth.

' 6. An apparatus as claimed in claim 5, and comprising means for forcing the fibrous pulp from the container to the mould, as set forth.

7. An apparatus for manufacturing hollow bodies from fibrous pulp, comprising in combination a container of variable capacity,

a supply pipe for supplying pul to the container, a pervious mould, a connecting pipe between the container and the mould, a valve in the said supply pipe, a valve in the said connecting pipe, means for removing the residual liquid from the mould and means for admitting a gaseous heating medium directly into the mould, as and for the purpose set forth.

8. An apparatus as claimed in claim 5 and comprising means for admitting a gaseous pressure medium into the container, as set forth. 7, 1

In testimony whereof I have signed my' name to this specification;

DB. Inc. RUDOLF HAAS. 

